Modified Rice Husk Waste‐Based Filter for Wastewater Treatment: Pilot Study and Reuse Potential

Abstract

This study investigates a rice husk waste‐based filter (RHW‐BF) for the treatment of graywater (GW) and primary treated wastewater (PTW). The RHW‐BF comprises three layers: coarse sand, chemically modified rice husk (MRH), and gravel. Continuous runs (Run I, II, III) assessed chemical oxygen demand, total suspended solids, total dissolved solids, and turbidity removal. Run (I) for GW achieved high removal: 73.7 %, 73.4 %, 74.6 %, and 92.6 %. Subsequent runs showed decreasing efficiencies due to media saturation. Similar trends occurred for PTW, with Run (I) achieving significant removal: 70.3 %, 69.0 %, 44.2 %, and 90.2 %. MRH particles played a crucial role in sustainable pollutant removal. The study compares treated wastewater with the World Health Organization and Egyptian limits, demonstrating its suitability for reuse in irrigation, agriculture, or sewer discharge.